Tobacco and dust separating apparatus



0. E. EISSMANN TOBACCO AND DUST SEPARATING APPARATUS Filed April 6, 1953July 24, 1956 2 Sheets-5heet l INVENTOR OSWALD ERIGH EISSMANN Mix!ATTORN EY July 24, 1956 0. E. EISSMANN 2,755,930

TOBACCO AND DUST SEPARATING APPARATUS Filed April 6 1951 2 Sheets-Sheet2 INVENTOR OSWALD ERICH EISSMANN BMJM ATTORNEY United States Patent2,755,930 TOBACCO AND DUST SEPARATING APPARATUS Oswald Erich Eissmann,Richmond, Va., assignor to American Machine & Foundry Company, acorporation of New Jersey Application April 6, 1951, Serial No. 219,551Claims. (Cl. 209-139) This invention relates to an improved tobacco anddust separating apparatus.

Heretofore a number of developments have been made in this field whichhave been found to have a number of disadvantages in operation. It hasbeen found that con veyed tobacco has a tendency to roll up in lumps atcertain areas of the separating apparatus and after reaching a size tooheavy to be supported by the air stream it falls downwardly in a biglump which is too large to be effectively separated. As a result themachine either clogs up or a good portion of the bunched material isdischarged into the wrong separating chamber.

Another disadvantage has been that small diameter cyclone separatorshave had a tendency to clog and they have been so disposed with respectto the separator that they have not been readily replaceable to removeclogged or Worn out separators.

It is therefore an object of this invention to provide an apparatuswherein the air intake gates are so arranged that tobacco will not ballup or roll up into rolls during the processing of the tobacco throughthe machine.

A further object is to provide a dust separating chamber wherein therewill be a more uniform and large area over which dust laden air isextracted from the dust separating chamber.

A further object is to provide cyclone separators which will have theirintake ducts mounted across the entire back of a tobacco separatingapparatus.

A further object is to provide a tobacco separator wherein a bank ofsmall diameter separators are readily replaceable.

Another object is to provide an air separating passageway which willefiiciently separate stems from lamina without causing tobacco to bunchup.

A further object is to provide and associate small diameter cycloneseparators with a tobacco separating apparatus which will be of suchdesign and construction that the dust is separated along a path oftravel which is sub stantially in a straight line.

' Other objects and features of the invention will appear as thedescription of the particular physical embodiment selected to illustratethe invention progresses. In the accompanying drawings, which form apart of this specification, like characters of reference have beenapplied to corresponding parts throughout the several views which makeup the drawings.

In the accompanying drawings:

Fig. 1 is a sectional side elevation of the improved tobacco and dustseparating apparatus,

Fig. 2 is a partial sectional end elevation, taken on line 2 of Fig. 1,illustrating the arrangement of the dust and air receiving ducts of thefilter tubes at the rear end of the machine, and

Fig. 3 is an isometric view of a single filter tube.

With reference to Figure 1, the tobacco and dust separating apparatusconsist of a tobacco separator housing H, a detachable dust separatorunit D, and a suitable source of suction E.

In operation, the unstemmed tobacco leaves T are deposited into aninclined feed chute 10 which delivers it into the pockets of a revolvinggate valve 12. The latter, by means of another inclined chute 14, feedssaid tobacco into the path of suitable combs 16 secured to a revolvingdrum 18. Combs 16, coacting with stationary rakes 20, 21 and 23 and aplurality of spaced semi-circular serrated bars 22 surrounding saiddrum, cause the lamina to be torn from the stem portion of the leaves ina manner shown and described inmy copending application S. N. 51,211filed September 25, 1948, now Patent No. 2,701,570.

Tearing of the lamina from the stem takes place when the combs 16 firstengage with the tobacco leaves. tional tearing takes place when theleaves are forwarded past stationary rakes 20, 21 and 23 and serratedbars 22.

The torn tobacco and stem portion drop through the 7' spaces between theserrated bars 22 onto a continuously moving belt 24 which hurls the torntobacco and stem pieces toward an adjustable wall 26 into the air streamentering the separating apparatus at location A. The air stream iscreated by the suction system E and the torn'tobacco is carried throughthe separating housing H by the air stream in the direction of thearrows shown' in Figure 1.

The stem portions which have been stripped clean of leaf lamina ofcourse are heavier than the lamina and therefore offer no resistance tothe lifting action of the incoming air stream. As a result the stemsdrop through said opening of the housing into a suitable box or receplamina and the stem portions tacle B. The pieces of which still havesome lamina adhering thereto after being thrown 01f the belt 24 areintercepted by the incoming air stream and carried upward between theadjustable wall 26 and an air stream guide plate 28 in the direction ofthe arrows.

The guide plate 28 serves the important purpose of re taining thevelocity of the air stream and preventing the stems with adheringtobacco from being pushed by the air stream back into the space betweenthe serrated bars 22 and belt 24.

It has been found that without guide plate 28 the velocity of the airstream, entering from a substantially narrower opening, decreasesbecause of the larger. space between the bars 22 and belt 24 to such anextent that the stems with adhering tobacco tumble downward'agai'n andfall out of the air stream back onto the belt and the tobacco carriedthereon. bulence and started to entangle the tumbling tobacco with thenewly arriving tobacco which resulted in a rolling action of the entiremass.

During this rolling action the stem portions engaged with a certainamount of free lamina and created a lump or ball similar to a snowballrolling down a' hillside.

After this lump become too big and heavy for the air' stream to supportand roll, it simply dropped out of the opening of the incoming air andeven sometimes choked the machine.

I have found that I have overcome this difliculty by with adheringtoadding guide plate 28 and the stems bacco are carried upward and aredeflected backby the deflector wall 30 into the range of action of theshredding drum 18 to be reprocessed. It will thus be seen that onlyclean individual stems fall out of the opening A into the chute orreceptacle B.

All lamina including that hurled by centrifugal force from the shreddingdrum 18 travels upward and around the horizontal bend 30 of theseparator housing H. In-

completely stemmed tobacco is deflected back to the thresher in themanner described and claimed in my 00- 51,211 filed September 25,-

pending application, S. N. 1948, now Patent No. 2,701,570. The verticalforward Patented July 24, s

Addi

Such movement created a tur-' wall 32 of vertical shaft 34 of saidhousing H is provided with an air inlet door 36 which opens up outwardlyand permits a predetermined amount of air to enter into the separatingchamber at this point. Door 36 is made of three sections and is shownand described in my copending application S. N. 729,818 filed February20, 1947, now Patent No. 2,643,768. This door is provided for thepurpose of controlling the amount of air in the vertical shaft of theseparator housing H. I have found while it serves the purpose for whichis was intended the incoming air stream traveling in substantially thesame direction as the original one, often reenforced the latter streamto such an extent that it lifted up everythihng in its upward straightpathincluding undesirable light weight stems.

To eliminate this undesirable action and also to avoid the occasionalobjectionable accumulation of tobacco on the top surface of thestationary air stream guide plate 38, another three sectional door 40 isprovided. The latter is of substantially the same design as the doors36, but doors 40 open inwardly and cause the incoming air stream to movedownwardly and somewhat intercepting the up coming air stream and at thesame time offsetting the air stream entering through doors 36. It isvery noticeable that this combination or action of the intercepting airstreams results in a very desirable turbulence with the effect ofspreading the tobacco in the separator housing over a much greater areaand causing torn tobacco leaves to bounce in a crisis-cross, back andforth, and up and down manner thereby resulting in a greater quantity ofcleaner finished tobacco as well as a marked increase in separatingefiiciency.

The pieces of lamina thus cleaned float upward and into the rearchambers of the separator housing H provided at its lowermost portionwith a suitable rotating gate valve 44 which is of substantially thesame design and construction as the one shown in my copendingapplication S. N. 51,211, and which deposits the cleaned lamina onto asu'table conveyor C. The rear chamber of the separator housing H is alsoprovided with an inclined perforated plate 46 which permits any sand orheavy dust particles to drop through the perforations of said plate intoa suitable chute 48 which leads to a suitable screw conveyor 50. Theaccumulated material is forwarded to a suitable gate valve 52 whichdischarges the material into a. collector or receptacle 54. The rearportion of said rear chamber is also provided with suitable screens 56through which the dust laden air is exhausted and which separates lint,string and feathers from the air stream in this area.

The rear wall of the tobacco separator housing is formed by thedetachable mounted dust separating unit D which consists of a clean airsuction shaft 61) and a dust collecting chamber 62. Within the suctionshaft 60 are detachably mounted and arranged a plurality of speciallydesigned cyclone type is provided with a tangentially arranged inletduct 66 which at its free end is secured to a corresponding opening 69(Fig. 2) in the front wall 70 of the unit D which, as men oned above,forms the rear wall of the seperator housing H. This arrangement has theadvantage that air velocity in the separating chamber S is uniformlylowered over the entire width of the area and there is no tendency forthe air stream to be directed toward any particular outlet. This hasresulted in improved separating efficiency in this part of the machine.

Each dust separator 64 is therefore connected to the rear portion ofsaid housing H. The inlet duct 66 of each dust separator 64 is connectedto and blends in with the top end of a cylindrical housing 68 of thesame in a tangential and spiral fashion as illustrated in Fig. 3. Thecylindrical housing 68 (Fig. 3) on its lower end is provided with aconical portion 72, the open free end of which is attached to acorresponding opening 74 formed in the rear wall 75 of the suction shaft60. Into the otherwise closed top portion of the cylindrical housing 68dust separators 64 each of which protrudes a tube 76 held in a suitablemanner in the center of and coaxial with the housing 68.

As the dust laden air enters the tangential inlet duct 66 of eachseparator 64 it is caused to spin around within the housing 68 in thecylindrical space formed by its outer walls and tube 76. This spinningaction results in centrifugal force separating the dust from the air andthe dust, being heavier, drops out of the open'conical portion- 72 ofsaid housing while the clean air is exhausted from said cylindricalhousing through the tube 76 into the clean air suction shaft 60. Thelower portion of the latter is suitably connected to one or moresuctionfans 80 which, through a suitable exhaust shaft 82 discharge theclean air back into the room from which it was taken. Each exhaust fan80 is driven by a motor M as illustrated in Fig. 1.

The dust discharged from the opening of each conical end portion 72 ofeach separator drops into the dust collecting chamber 62 which, at itslower portion is connected to a detachable hopper 84 having a suitablescrew conveyor 86 which delivers the dust to a rotating gate valve 88which deposits said dust into a receptable 90.

The eflicient and eifective operation of the dust separators 64 lies intheir unique design and arrangement. The dust after being separated fromthe air within the cylindrical housing 68 is permitted to keep movingand is discharged ,in substantially the same direction as it enteredsaid housing without being guided around corners or curves. Thiseliminates the possibility of dust collecting and eventual choking ofthe dust separators which has been one of the principal disadvantages ofcyclone type separator up to this moment and especially with tobaccodust.

In order to remove any dust particles which pass through the screens 56and do not reach the separators 64 but settle downwardly along wall 70,I have provided, a collectorthrough 92 provided with a screw conveyor 94to deliver such dust to a rotating gate valve 96 which in turn depositsthe same into a suitable receptacle 98.

For cleaning, inspection and maintenance purposes, the rear wall of thedust collecting chamber 62 is provided with a door 100.

Inorder to provide the dust filter tubes 64 with an'adequate volume ofair to maintain their efficiency, the top side of the separator housingH may be provided with an opening 57 to permit additional air to enterat this point. The-amount of air entering through said opening may becontrolled by a suitable door 59 mounted on a cross shaft 61 carrying aworm wheel 63 meshing with a worm which is actuated by a suitable handle67. By turn! ing said handle clockor anti-clockwise, the door 59 may beopened or closed as desired. This feature is more completely describedand claimed in my copending application S. N. 51,211 referred to above.

The bank of cyclone separators forming the rear wall of the collectingchamber 62 may be quickly replaced by disconnecting the brackets 71which secure it to the rear of the separator.

The invention above described may be varied in construction within thescope of the claims, for the particular device selected to illustratethe invention is but one of many possible embodiments of the same. Theinvention, therefore, it not to be restricted to the precise details ofthe structure shown and described.

What is claimed is:

1. A classifying apparatus for separating tobacco stems, tobacco leaflamina, sand, and dust into separate categories, said apparatuscomprising a housing, an air passageway mounted in said housing andhaving areas for separating out said material into different categories,an airintake opening for allowing air to enter one end of saidpassageway, means for delivering a supply of torn tobacco to said airpassageway, one of said separating areas being connectedtosaidpassageway near the air intake opening for removing tobacco stemsfrom said torn tobacco, an

other of said areas being an expanded chamber connected near the otherend of said air passageway for separating tobacco leaf lamina from saidair stream, a source of suction connected to said other end for movingan air stream with suspended material through said separating areas andthrough a bank of small diameter cyclone separators, means for removingthe separated lamina from said chamber, and a bank of small diametercyclone separators having their intake ducts mounted at regularly spacedintervals across one wall of said chamber for effecting a Withdrawal ofair from said chamber over a wide area to separate fine sand and dustfrom the air stream, means for collecting said fine sand and dust fromsaid cyclone separators, and a screen positioned between said expandedchamber and said intake ducts to prevent lamina from entering saidducts.

2. A classifying and separating apparatus for separating tobacco leaflamina and dust into different categories, said apparatus comprising anair passageway, means for delivering torn tobacco leaves to saidpassageway, an enlarged, walled, separating area forming part of saidpassageway and located at one end thereof, a plurality of small diametercyclone dust separators having intake ducts mounted directly over a widearea of one wall of said enlarged separating area to effect a withdrawalof air from said separating chamber uniformly over a wide area of saidwall, a screen interposed in said air passageway between said separatingchamber and said intake ducts to prevent lamina from being drawn intosaid cyclone separators, and a source of suction for moving a stream ofair carrying said torn tobacco leaf lamina through said air passageway,through said enlarged separating chamber and said small diameter cycloneseparators to separate lamina in said enlarged separating area from thestream of air and then to separate dust from said stream of air.

3. A classifying apparatus for separating torn tobacco leaves intodifferent categories, said apparatus comprising a housing, an airpassageway formed in said housing, means for moving a stream of airthrough said passageway, an air intake opening formed at one end of saidpassageway through which air enters said passageway, a portion of saidpassageway extending above and below said opening, means for dischargingtorn tobacco leaves into said air stream at a position adjacent saidopening to allow stems without lamina to fall downwardly while causinglamina without stems to be drawn upwardly, an enlarged separatingchamber forming part of said air passageway, a bank of small diameterseparators detachably secured to and forming a wall of said separatingchamber wherein said separators are uniformly spaced over the entiresurface of said wall, the intake inlets of said small diameterseparators being connected directly to openings formed in the wall ofsaid separating chamber over a wide area thereof to effect a withdrawalof air from said separating chamber over a large wall area, and a laminaseparating screen positioned across the air stream at a point upstreamof said small diameter separators between said enlarged separatingchamber and said intake inlets of said small diameter separators forpreventing lamina from reaching said separators.

4. A separating apparatus comprising a housing, an air passageway formedin said housing, means for discharging torn tobacco leaves into avertical portion of said air passageway, an air intake positioned abovesaid means for causing air to enter said passageway at an angle whichdirects the air initially towards the means for discharging torn tobaccoleaves into said air passageway to prevent tobacco from beingaccumulated in lumps in said air passageway, a second inlet having adownwardly extending door positioned above said air intake andswingingly mounted for movement in an outward direction from said airpassageway to cause air to enter said passageway from the outsideatmosphere in an upward direction to assist in pushing clean lamina upalong said passageway, a separating chamber connected with and of largercross sectional area than said air passageway for removing clean tobaccoleaf lamina from the air stream, a bank of small diameter cycloneseparators having their intake ducts individually connected and spaceduniformly apart and having such a number of small diameter cycloneseparators as to completely cover one wall of said separating chamberfor effecting the withdrawal of air from said chamber over a relativelywide surface area, a lamina separating screen mounted across said airstream at a position upstream of said small diameter separators betweensaid separating chamber and said bank of small diameter separators toprevent lamina from reaching said separators, and a source of power forforwarding a stream of air through said air passageway.

5. A tobacco separating apparatus wherein an air passageway is providedfor confining an air stream to a predetermined path of travel in ahousing, said passageway having a vertical portion, a tobacco dischargedevice mounted in the housing for delivering torn tobacco to saidpassageway, said air passageway including an upwardly directed ductpositioned adjacent the tobacco discharge device to receive said torntobacco discharged from said device, the cross-sectional area of thepassageway being such that it is substantially uniform, and means formoving a stream of air upwardly through the duct and through thepassageway at such a velocity that clean stems fall downwardly throughthe duct while lamina and stems with lamina are drawn upwardly by theair stream, an air intake positioned above said discharge device todirect air downwardly towards said discharge device to prevent tobaccofrom accumulating in lumps in front of said discharge device, a secondair intake positioned above said first named intake and having adownwardly extending, outwardly swinging door to cause air to enter saidpassageway from the outside atmosphere in an upward direction to assistin pushing clean lamina up along said passageway, an enlarged chamberconnected to said air passageway to allow lamina to settle out of saidair stream, a bank of small diameter cyclone separators having theirintake ducts dispersed across one wall of said separating chamber toeffect a withdrawal of air from said chamber over a relatively widesurface area, and a screen positioned between said separating chamberand said intake ducts to prevent lamina from entering said ducts.

References Cited in the file of this patent UNITED STATES PATENTS1,888,372 Bramwell Nov. 22, 1932 2,050,765 Rundell Aug. 11, 19362,163,833 Eissmann June 27, 1939 2,173,087 Eissmann Sept. 19, 19392,173,088 Eissmann Sept. 19, 1939 2,208,896 Dahlstrom July 23, 19402,257,552 Hammack Sept. 30, 1941 2,643,737 Bowers June 3.0, 1953 FOREIGNPATENTS 93,386 Sweden July 1. 1938

